Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “coding change”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 847 records · Page 47Linked to original sources

A group of related cDNAs encoding secreted proteins from Hessian fly [Mayetiola destructor (Say)] salivary glands.

A group of cDNAs has been isolated and characterized from Hessian fly [Mayetiola destructor (Say)] salivary glands. Members in this group appear to encode proteins with secretion signal peptides at the N-terminals. The mature putative proteins are small, basic proteins with calculated molecular weights that ranged from 8.5 to 10 kDa, and isoelectric points from 9.92 to 10.90. Sequence analysis indicated a strong selection for mutations that generate amino acid changes within the coding region. Northern blot analysis revealed that these genes are expressed only in the first instar larvae, a critical stage that determines if the interaction between a specific Hessian fly biotype and a specific wheat cultivar is compatible. Genomic analysis demonstrated that multiple copies of similar genes are clustered within a short region on chromosome 2A. This is the same arm in which two avirulence genes have been mapped.

Amino Acid Sequence↗

Association between ventilation rates in 390 Swedish homes and allergic symptoms in children.

UNLABELLED: The aim of the study was to test the hypothesis that a low-ventilation rate in homes is associated with an increased prevalence of asthma and allergic symptoms among children. A total of 198 cases (with at least two of three symptoms: wheezing, rhinitis, eczema) and 202 healthy controls, living in 390 homes, were examined by physicians. Ventilation rates were measured by a passive tracer gas method, and inspections were carried out in the homes. About 60% of the multi-family houses and about 80% of the single-family houses did not fulfill the minimum requirement regarding ventilation rate in the Swedish building code (0.5 air changes per hour, ach). Cases had significantly lower ventilation rates than controls and a dose-response relationship was indicated. PRACTICAL IMPLICATIONS: A low-ventilation rate of homes may be a risk factor for allergies among children. Families with allergic children should be given the advice to have good ventilation in the home. In investigations, of associations between environmental factors and allergies, the air change rate in homes has to be considered.

Asthma↗

A mutation in the prion protein gene in Creutzfeldt-Jakob disease in Jewish patients of Libyan, Greek, and Tunisian origin.

A modified host protein encoded by the gene specifying the scrapie amyloid precursor is critically involved in the pathogenesis of transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease (CJD), Gerstmann-Straussler-Scheinker's syndrome, and Kuru. A mutation in the open reading frame of this gene was recently described in a cluster of patients with CJD in Slovakia. This mutation at codon 200 changes glutamic acid coded by GAG to lysine coded by AAG. We examined the prevalence of this mutation in the cluster of patients with CJD among Sephardic Jews of Libyan descent in Israel. A polymerase chain reaction was used to amplify the open reading frame of the prion protein gene from DNA extracted from frozen brain tissue of five Israeli residents (four of Libyan and one of Greek origin) and two familial cases in Jews born in Greece and Tunisia who later emigrated to France. The existence of the codon 200 mutation was detected by digestion of the open reading frame fragments with the BsmA1 restriction enzyme. All patients had the same codon 200 mutation. These findings implicate this mutation in the high prevalence of CJD among Libyan and Sephardic Jews from other Mediterranean countries.

Creutzfeldt-Jakob Syndrome↗

Changes in intensity discrimination following monaural long-term use of a hearing aid.

Previous work has shown that a normally aided ear tested without the hearing aid is better able to identify speech-in-noise than the unaided ear at high sound levels, while performance for the unaided ear is superior at lower sound levels [S. Gatehouse, J. Acoust. Soc. Am. 86, 2103-6 (1989); J. Acoust. Soc. Am. 92, 1258-68 (1992)]. This effect was further explored using intensity discrimination for complex stimuli. Stimuli were half-octave bandpass-filtered tone complexes centered at 0.25 and 3 kHz. Four bilateral, symmetric hearing-impaired listeners with mean HL of 24 dB at 0.25 kHz, and 58 dB at 3 kHz were tested. Intensity discrimination was performed across the dynamic range of the listeners. At sound-pressure levels greater than 85 dB, the normally aided ear tested without the aid was more sensitive to changes in intensity than the unaided ear, whereas at lower levels, the converse occurred. This pattern was observed only for the 3-kHz center frequency, and not for the 0.25-kHz center frequency. Insertion gain measurements using the aids at normal volume showed an average of 20 dB gain at 3 kHz, and -2 dB gain at 0.25 kHz. The changes in intensity discrimination in the normally aided ear are consistent with the frequency-gain characteristics of the hearing aid, and suggest that a change in intensity coding occurred.

Adolescent↗

Revertant analysis of J-K mutations in the encephalomyocarditis virus internal ribosomal entry site detects an altered leader protein.

The internal ribosomal entry site (IRES) of picornaviruses consists of various sequence and structural elements that collectively impart translational function to the genome. By engineering substitution and deletion mutations into the J-K elements of the encephalomyocarditis virus IRES, translationally defective viruses with small-plaque phenotypes were generated. From these, 60 larger-plaque revertant viruses were isolated and characterized, and their sequences were compared with a structural model of the IRES. The data provide confirming evidence for the existence of helix J3 within stem J but suggest that helix J1 is 3 bp longer than previously estimated. They also suggest that previously modeled stems L and M should be replaced by an alternative structure. One reversion mutation was mapped to the leader protein coding region. This change of leader amino acid 20 from Pro to Ser increased the viral plaque size dramatically but did not alter the cell-free translational activity of the mutated, parental IRES.

Animals↗

Independence of evolutionary and mutational rates after transmission of avian influenza viruses to swine.

In 1979, an H1N1 avian influenza virus crossed the species barrier, establishing a new lineage in European swine. Because there is no direct or serologic evidence of previous H1N1 strains in these pigs, these isolates provide a model for studying early evolution of influenza viruses. The evolutionary rates of both the coding and noncoding changes of the H1N1 swine strains are higher than those of human and classic swine influenza A viruses. In addition, early H1N1 swine isolates show a marked plaque heterogeneity that consistently appears after a few passages. The presence of a mutator mutation was postulated (C. Scholtissek, S. Ludwig, and W. M. Fitch, Arch. Virol. 131:237-250, 1993) to account for these observations and the successful establishment of an avian H1N1 strain in swine. To address this question, we calculated the mutation rates of A/Mallard/New York/6750/78 (H2N2) and A/Swine/Germany/2/81 (H1N1) by using the frequency of amantadine-resistant mutants. To account for the inherent variability of estimated mutation rates, we used a probabilistic model for the statistical analysis. The resulting estimated mutation rates of the two strains were not significantly different. Therefore, an increased mutation rate due to the presence of a mutator mutation is unlikely to have led to the successful introduction of avian H1N1 viruses in European swine.

Animals↗

Establishment of a rescue system for canine distemper virus.

Canine distemper virus (CDV) has been rescued from a full-length cDNA clone. Besides Measles virus (MV) and Rinderpest virus, a third morbillivirus is now available for genetic analysis using reverse genetics. A plasmid p(+)CDV was constructed by sequential cloning using the Onderstepoort vaccine strain large-plaque-forming variant. The presence of a T7 promoter allowed transcription of full-length antigenomic RNA by a T7 RNA polymerase, which was provided by a host range mutant of vaccinia virus (MVA-T7). Plasmids expressing the nucleocapsid protein, the phosphoprotein, and the viral RNA-dependent RNA polymerase, also under control of a T7 promoter, have been generated. Infection of HeLa cells with MVA-T7 and subsequent transfection of p(+)CDV plus the helper plasmids led to syncytium formation and release of infectious recombinant (r) CDV. Comparison of the rescued virus with the parental virus revealed no major differences in the progression of infection or in the shape and size of syncytia. A genetic tag, consisting of two nucleotide changes within the coding region of the L protein, has been identified in the rCDV genome. Expression by rCDV of all the major viral structural proteins has been demonstrated by immunofluorescence.

Animals↗

Enhancement of capsid gene expression: preparing the human papillomavirus type 16 major structural gene L1 for DNA vaccination purposes.

Expression of the structural proteins L1 and L2 of the human papillomaviruses (HPV) is tightly regulated. As a consequence, attempts to express these prime-candidate genes for prophylactic vaccination against papillomavirus-associated diseases in mammalian cells by means of simple DNA transfections result in insufficient production of the viral antigens. Similarly, in vivo DNA vaccination using HPV L1 or L2 expression constructs produces only weak immune responses. In this study we demonstrate that transient expression of the HPV type 16 L1 and L2 proteins can be highly improved by changing the RNA coding sequence, resulting in the accumulation of significant amounts of virus-like particles in the nuclei of transfected cells. Data presented indicate that, in the case of L1, adaptation for codon usage accounts for the vast majority of the improvement in protein expression, whereas translation-independent posttranscriptional events contribute only to a minor degree. Finally, the adapted L1 genes demonstrate strongly increased immunogenicity in vivo compared to that of unmodified L1 genes.

Capsid Proteins↗

Venous thromboembolism in infancy and childhood.

A retrospective study of Scottish hospital inpatients aged 15 years or less has revealed, over a 4-year period, 36 cases of venous thrombosis or phlebitis. Of these 10 were considered to have deep venous thrombosis; 2 cases were associated with obvious pulmonary embolism and 2 cases developed chronic venous insufficiency. change in the coding allocations are proposed. There are "high risk" situations in childhood disease in which a diagnosis of venous thromboembolic disease should be considered and investigated.

Adolescent↗

Role of the MHC2TA gene in autoimmune diseases.

OBJECTIVES: Expression of major histocompatibility complex (MHC) class II genes is almost exclusively regulated by the class II transactivator. A promoter polymorphism (-168A/G, rs3087456) in the MHC2TA gene was associated with increased susceptibility to rheumatoid arthritis, multiple sclerosis and myocardial infarction in a northern European population. However, no evidence of association of this MHC2TA variant with the two autoimmune diseases could be subsequently detected in independent cohorts. AIM: To test the aforementioned single nucleotide polymorphism and another G-->C change (nt1614 from coding sequence, rs4774) to analyse the haplotype pattern in this MHC2TA gene. METHODS: A case-control study was performed with 350 patients with rheumatoid arthritis, 396 patients with multiple sclerosis, 663 patients with inflammatory bowel disease (IBD) and 519 healthy controls from Madrid. Genotyping was ascertained by using TaqMan assays-on-demand on a 7900HT analyser, following the manufacturer's suggestions (Applied Biosystems, Foster City, California, USA). Haplotypes were inferred with the expectation-maximisation algorithm implemented by the Arlequin software. RESULTS: No independent association with these autoimmune diseases was found for either polymorphism in the Spanish cohorts tested. However, when haplotypes were compared between patients with rheumatoid arthritis and controls, a significant difference in their overall frequency distribution was observed, evidencing a protective haplotype (-168A/1614C, p = 0.006; odds ratio (OR) 0.7) and a risk haplotype (-168G/1614C, p = 0.019; OR 1.6). Patients with multiple sclerosis mirrored these results, but no effect on IBD was identified. CONCLUSIONS: The MHC2TA gene influences predisposition to rheumatoid arthritis and multiple sclerosis, but not to IBD. The -168G allele is not an aetiological variant in itself, but a genetic marker of susceptibility/protection haplotypes.

Arthritis, Rheumatoid↗

Intrafamilial phenotypic variability in families with RDS mutations: exclusion of ROM1 as a genetic modifier for those with retinitis pigmentosa.

OBJECTIVES: To identify suspected RDS mutations in families in which different people have been identified with either generalised retinal dystrophy or macular dystrophy. METHODS: Two families with a retinal dystrophy were extensively phenotyped and blood was taken for mutation analysis of the RDS (all) and ROM1 (retinitis pigmentosa patients only) genes. RESULTS: A novel p.Trp94X mutation in RDS was found in all three affected members of a two-generation family that was associated with retinitis pigmentosa in the son, pattern dystrophy in the daughter and fundus flavimaculatus in the mother. In the second family, the proband with retinitis pigmentosa carried a p.Arg220Trp mutation. The mother, who was unavailable for mutation screening, had adult vitelliform macular dystrophy. No ROM1 mutations were found in those with retinitis pigmentosa in either family. CONCLUSION: Mutations in RDS can be associated with an intrafamilial variation in retinal disease. The phenotypes range from Stargardt-like macular dystrophy to classic retinitis pigmentosa. CLINICAL RELEVANCE: Intrafamilial phenotypic variation may be due to the presence of environmental or genetic modifying factors. The presence of a modifying-sequence change in the coding region of ROM1 for two people with retinitis pigmentosa from two families with intrafamilial variation in RDS mutation phenotype has been excluded in this study.

Adult↗

Analysis of visual field progression in glaucoma.

BACKGROUND: Despite the widespread use of computerised perimetry the diagnosis of visual field deterioration in following glaucoma patients over time remains particularly difficult. A new method of analysis using a novel graphical display of longitudinal field data is presented. METHODS: A linear regression model of the luminance sensitivity at each stimulus location against time of follow up transforms the quantitative data from a series of fields into a colour coded form which illustrates the spatial configuration of change to aid the interpretation of field loss. The method of analysis and the developed computer software (PROGRESSOR) is described. Comparison with STATPAC-2 glaucoma change probability analysis is given including levels of agreement between the techniques using series of fields of 10 eyes from patients with normal tension glaucoma. RESULTS: Examples of this new method compare well with STATPAC-2 analysis. The level of agreement between the techniques to separate progressing from stable retinal locations is good (kappa = 0.62; SE = 0.04). CONCLUSIONS: This new technique, which combines the change in perimetric sensitivity over time with colour coding of significant change into one image may provide an efficient method to detect true progression in glaucomatous field loss.

Diagnosis, Computer-Assisted↗

Incidence of inflammatory bowel disease in Scottish children between 1968 and 1983; marginal fall in ulcerative colitis, three-fold rise in Crohn's disease.

Linked hospital admission data for 1968-1983 were used to identify 723 children aged 16 years or less at the time of first admission to any Scottish hospital with an ICD coded diagnosis of Crohn's disease (282) or ulcerative colitis (441). The accuracy of the coded diagnoses was checked by examination of the hospital notes of 144 patients. The coded diagnosis was incorrect in 11/83 coded as Crohn's disease and 13/61 as ulcerative colitis; frequency of incorrect coding did not change significantly with time. Despite an 18% fall in the population aged less than or equal to 16 during this time, the number of new cases of Crohn's disease rose from 10 in 1968 to 28 in 1983. Thus the recorded incidence of Crohn's disease in Scottish children has risen more than three-fold in 16 years, from 6.6 to 22.9 per million (p less than 0.0001), with no difference between the sexes. Parallel data for ulcerative colitis were rendered inaccurate by miscoding of infective gastroenteritis as colitis. In an attempt to reduce this source of error cases aged five years and under were excluded from analysis, resulting in an incidence of 19.1 cases per million aged six to 16 in 1968 and 15.6 in 1983, not a significant change (r = 0.42, p = 0.052). When males and females were analysed separately, however, there was a significant decrease in the incidence of UC in male children (r = -0.4, p = 0.028), with no change for female children (r = 0.1, p = 0.595).

Adolescent↗

Morbidity and mortality in motor neuron disease: comparison with multiple sclerosis and Parkinson's disease: age and sex specific rates and cohort analyses.

The cause of motor neuron disease (MND) remains unknown although recent reports have suggested a possible rise in mortality rate. The present account describes age-specific patterns in morbidity rate and cross-sectional and cohort analyses of mortality rate, and compares these with those in multiple sclerosis and Parkinson's disease. First hospital admission rate for motor neuron disease (a proxy for incidence rates) rose steadily with age in males and females until the age of 75 years or more, but then fell, but only in females. This irregular pattern suggested the possibility of an environmental effect on certain older birth cohorts. The validity of the results was supported by a similar pattern in the two hospital regional authorities studied and the difference between this pattern and that found in multiple sclerosis and Parkinson's disease. Age-specific mortality rates of motor neuron disease between 15 and 64 years for males and females in England and Wales from 1940 to 1982 rose steadily with age. Mortality rates after the age of 65 fell in all female cohorts studied, but only in the earlier male cohorts. Unlike Parkinson's disease there was no strong birth cohort effect. However an analysis of Office of Population Censuses and Surveys (Registrar General) reports has revealed a slight increase in the age-specific mortality rate in both males and females aged 65 and over for successive birth cohorts born since 1900. Neither changes in ICD coding or in diagnostic habits could account for this pattern, which differed from that seen in Parkinson's disease. No such effect was seen in multiple sclerosis.

Adult↗

How the health belief model helps the tobacco industry: individuals, choice, and "information".

OBJECTIVE: To analyse trial and deposition testimony of tobacco industry executives to determine how they use the concepts of "information" and "choice" and consider how these concepts are related to theoretical models of health behaviour change. METHODS: We coded and analysed transcripts of trial and deposition testimony of 14 high-level executives representing six companies plus the Tobacco Institute. We conducted an interpretive analysis of industry executives' characterisation of the industry's role as information provider and the agency of tobacco consumers in making "choices". RESULTS: Tobacco industry executives deployed the concept of "information" as a mechanism that shifted to consumers full moral responsibility for the harms caused by tobacco products. The industry's role was characterised as that of impartial supplier of value-free "information", without regard to its quality, accuracy and truthfulness. Tobacco industry legal defences rely on assumptions congruent with and supported by individual rational choice theories, particularly those that emphasise individual, autonomous decision-makers. CONCLUSIONS: Tobacco control advocates and health educators must challenge the industry's preferred framing, pointing out that "information" is not value-free. Multi-level, multi-sectoral interventions are critical to tobacco use prevention. Over-reliance on individual and interpersonal rational choice models may have the effect of validating the industry's model of smoking and cessation behaviour, absolving it of responsibility and rendering invisible the "choices" the industry has made and continues to make in promoting the most deadly consumer product ever made.

Choice Behavior↗

Allergic inflammation-induced neuropeptide production in rapidly adapting afferent nerves in guinea pig airways.

In the vagal-sensory system, neuropeptides such as substance P and calcitonin gene-related peptide (CGRP) are synthesized nearly exclusively in small-diameter nociceptive type C-fiber neurons. By definition, these neurons are designed to respond to noxious or tissue-damaging stimuli. A common feature of visceral inflammation is the elevation in production of sensory neuropeptides. Little is known, however, about the physiological characteristics of vagal sensory neurons induced by inflammation to produce substance P. In the present study, we show that allergic inflammation of guinea pig airways leads to the induction of substance P and CGRP production in large-diameter vagal sensory neurons. Electrophysiological and anatomical evidence reveals that the peripheral terminals of these neurons are low-threshold Adelta mechanosensors that are insensitive to nociceptive stimuli such as capsaicin and bradykinin. Thus inflammation causes a qualitative change in chemical coding of vagal primary afferent neurons. The results support the hypothesis that during an inflammatory reaction, sensory neuropeptide release from primary afferent nerve endings in the periphery and central nervous system does not require noxious or nociceptive stimuli but may also occur simply as a result of stimulation of low-threshold mechanosensors. This may contribute to the heightened reflex physiology and pain that often accompany inflammatory diseases.

Adaptation, Physiological↗

Quantitative analysis of firing properties of pyramidal neurons from layer 5 of rat sensorimotor cortex.

Quantitative aspects of repetitive firing evoked by injected current steps and ramps were studied in layer 5 pyramidal neurons in brain slices of rat sensorimotor cortex to answer the following questions. Do the tonic firing properties of burst-firing and regular-spiking (nonbursting) neurons differ significantly? Does burst firing denote a discrete class of neurons or represent a continuum of firing properties? Is firing rate during the burst of action potentials related to stimulus amplitude? What aspect of the stimulus might the initial firing rate code? How stable are a neuron's firing properties over time? All recorded neurons fired tonically to a long-lasting current above a minimum value, and the tonic firing properties of most neurons were quite similar irrespective of their initial response to a current step. Only a group of high-resistance neurons had significantly different tonic firing properties. When slow current ramps (rising between 0.5 and approximately 20 nA/s) were applied, the relation between firing rate and current during the ramp was very similar to the relation between tonic firing rate and current obtained from long-lasting current steps. Low-resistance cells exhibited three distinct initial responses to a current step: fast adaptation, high-threshold bursts, and low-threshold bursts, observed in 54, 28, and 10% of recorded cells, respectively. High-resistance cells exhibited a distinctive slow adaptation of firing rate. Slowly adapting, fast-adapting (FA), and high-threshold burster (HTB) neurons exhibited no adaptation near the minimum current that evoked repetitive firing (I(o)). FA and HTB cells exhibited two-spike adaptation to a fina tonic firing rate during currents up to 1.6 times I(o). Only a higher current (2.1 times I(o)) evoked a burst in HTB cells, whereas a burst was evoked at I(o) in the low-threshold burster cells. In most cells analyzed, the initial firing rate, whatever its nature, increased monotonically with current step amplitude. The response to fast current ramps indicated that firing rate during adaptation or bursting may code rate of change of current. Repeated measurements during long-duration impalements indicated that both transient and tonic firing properties are stable over time. We discuss how the different tonic firing properties of large and small pyramidal neurons could be more important functionally than the different transient responses (burst/nonburst) of the large neurons. We conclude that the large neurons would perform a better linear transduction of time-varying synaptic current that reaches their somata. We compare the responses evoked by somatically injected current with those evoked by dendritic glutamate iontophoresis in previous studies.

Animals↗

The stress-responsive gene GADD45G is a functional tumor suppressor, with its response to environmental stresses frequently disrupted epigenetically in multiple tumors.

The CpG island of GADD45G was identified as a target sequence during the identification of hypermethylated genes using methylation-sensitive representational difference analysis combined with 5-aza-2'-deoxycytidine demethylation. Located at the commonly deleted region 9q22, GADD45G is a member of the DNA damage-inducible gene family. In response to stress shock, GADD45G inhibits cell growth and induces apoptosis. Same as other GADD45 members, GADD45G is ubiquitously expressed in all normal adult and fetal tissues. However, its transcriptional silencing or down-regulation and promoter hypermethylation were frequently detected in tumor cell lines, including 11 of 13 (85%) non-Hodgkin's lymphoma, 3 of 6 (50%) Hodgkin's lymphoma, 8 of 11 (73%) nasopharyngeal carcinoma, 2 of 4 (50%) cervical carcinoma, 5 of 17 (29%) esophageal carcinoma, and 2 of 5 (40%) lung carcinoma and other cell lines but not in any immortalized normal epithelial cell line, normal tissue, or peripheral blood mononuclear cells. The silencing of GADD45G could be reversed by 5-aza-2'-deoxycytidine or genetic double knockout of DNMT1 and DNMT3B, indicating a direct epigenetic mechanism. Aberrant methylation was further frequently detected in primary lymphomas although less frequently in primary carcinomas. Only one single sequence change in the coding region was detected in 1 of 25 cell lines examined, indicating that genetic inactivation of GADD45G is very rare. GADD45G could be induced by heat shock or UV irradiation in unmethylated cell lines; however, this stress response was abolished when its promoter becomes hypermethylated. Ectopic expression of GADD45G strongly suppressed tumor cell growth and colony formation in silenced cell lines. These results show that GADD45G can act as a functional new-age tumor suppressor but being frequently inactivated epigenetically in multiple tumors.

Antigens, Differentiation↗